The present invention relates to large vehicles having independent suspensions, such as those which are typically used in military applications and in large municipal vehicles, such as fire trucks. In particular, the invention relates to a frame and independent suspension assembly which allows a vehicle to have better stability by lowering the center of gravity, and better visibility because of the lower drivetrain and lower hoodline.
Military and other emergency vehicles must be designed to extremely demanding specifications. The vehicles must be capable of driving over or through obstacles which only a tactical or emergency driver would attempt. The vehicles must be able to endure corrosive, partially submerged and frequently dirty environments, such as standing water, chemicals or deep mud.
In addition, it is desirable for such vehicles to provide maximum forward visibility for the operator and maximum load carrying capacities. One step which has been taken in the design of heavy duty vehicles has been to utilize C-shaped channels as the main frame members. The use of two widely-spaced beams provides a space where various engine, transmission and other essential components can be mounted. Making more space available along the center line of the vehicle frame allows heavy components to be more effectively mounted at lower elevation which, in turn, lowers the vehicle's center of gravity. Vehicles with low centers of gravity have improved stability. A lower center of gravity in a vehicle provides improved resistance to overturning as the vehicle traverses rough terrain or maneuvers around obstacles at high rates of speed. The improved visibility that results from a lowering of a vehicle[']s drive train and hoodline allows for safer operation of the vehicle. While the present invention has particular application in the context of frame members which are C-shaped, the invention may be used with frame members having other shapes, such as tubular shapes (rounded and rectangular) and other structurally advantageous shapes.